Motor is a chevy 598 15-1 conv. headed. Running speedtech fogger 24n 20f and fuel at 5.75 plugs are NGK 10's. Motor is at 37deg and was pulling 9 out. pulled to the line and shut off at strip. Thanks for any help.
When you pull the 1/4 # of fuel the timing mark is likely to get a little more aggressive, which is ok. It is a little rich and a little under timed so the 1/4 # will clean both up. My guess is you are going to end up with 5- 5/14 FP to get that plug clean.
Not a bad start... But there's two ways to try it... One is to take a little fuel away and see if it picks up and shows more of a timing mark... The other way would be to add a degree of timing and see if the car picks up more and then recheck the timing mark as well as the fuel ring..
I myself have had the best luck making power when we can efficiently burn more fuel.. In this case you have a 24/20 as Speedtech calls there 150 HP deal.. You have a conv headed BBC and already have the timing back to 28 degrees. This by the laws of average is a little light in my notes.. The timing mark on the two plugs we can see are not quite even half way to the bend. usually a degree or two of timing seems to make more of a gain then taking away more fuel...
Just make a small change and go from there... Just my two cents.. SJ